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arXiv · 1707.04599

Finite size analysis of measurement device independent quantum cryptography with continuous variables

Panagiotis Papanastasiou·Carlo Ottaviani·Stefano Pirandola
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Abstract

We study the impact of finite-size effects on the key rate of continuous-variable (CV) measurement-device-independent (MDI) quantum key distribution (QKD). Inspired by the parameter estimation technique developed in [Rupert \textit{et al.} Phys. Rev. A \textbf{90}, 062310 (2014)]~we adapt it to study CV-MDI-QKD and, assuming realistic experimental conditions, we analyze the impact of finite-size effects on the key rate. We find that, increasing the block-size, the performance of the protocol converges towards the ideal one, and that block-sizes between $10^{6}$ and $10^{9}$ data points can already provide a key rate $\sim10^{-2}$ bit/use over metropolitan distances.

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Panagiotis Papanastasiou, Carlo Ottaviani, Stefano Pirandola. 2017-09-11. Finite size analysis of measurement device independent quantum cryptography with continuous variables. https://doi.org/10.1103/physreva.96.042332

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